/**
 * Copyright (c) 2008, Mu Dynamics.
 *  All rights reserved.
 *  
 *   Redistribution and use in source and binary forms, with or without modification, 
 *   are permitted provided that the following conditions are met:
 *   
 *  - Redistributions of source code must retain the above copyright notice, 
 *     this list of conditions and the following disclaimer.
 *  - Redistributions in binary form must reproduce the above copyright notice, 
 *     this list of conditions and the following disclaimer in the documentation and/or 
 *     other materials provided with the distribution.
 *  - Neither the name of the "Mu Dynamics" nor the names of its contributors may be used 
 *     to endorse  or promote products derived from this software without specific prior 
 *     written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND 
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
 * THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, 
 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package com.mu.jacob.core.model.decorator;

import java.util.List;

import javax.lang.model.element.Element;
import javax.lang.model.type.DeclaredType;
import javax.lang.model.type.TypeKind;
import javax.lang.model.type.TypeMirror;
import javax.lang.model.type.TypeVariable;
import javax.lang.model.type.TypeVisitor;
import javax.lang.model.type.WildcardType;

import com.mu.jacob.core.generator.Decorate;
import com.mu.jacob.core.generator.GeneratorException;

/**
 * TypeMirror decorator
 * @author Adam Smyczek
 *
 * @param <T>
 */
public class DefaultTypeMirror<T extends TypeMirror> extends DefaultDecorator<T> implements TypeMirror {

	/** The decorated type mirror */
	private T typeMirror;
	
	/**
	 * @see com.mu.jacob.core.model.decorator.DefaultDecorator#getDecorated()
	 */
	public T getDecorated() {
		return typeMirror;
	}

	/**
	 * @see com.mu.jacob.core.model.decorator.DefaultDecorator#getApiClass()
	 */
	@SuppressWarnings("unchecked")
	public Class<T> getApiClass() {
		return (Class<T>)TypeMirror.class;
	}

	/**
	 * @see com.mu.jacob.core.model.decorator.DefaultDecorator#initialize(java.lang.Object)
	 */
	public void initialize(T model) {
		this.typeMirror = model;
	}

	/**
	 * @see javax.lang.model.type.TypeMirror#accept(javax.lang.model.type.TypeVisitor, java.lang.Object)
	 */
	@Decorate
	public <R, P> R accept(TypeVisitor<R, P> v, P p) {
		return getDecorated().accept(v, p);
	}

	/**
	 * @see javax.lang.model.type.TypeMirror#getKind()
	 */
	public TypeKind getKind() {
		return getDecorated().getKind();
	}

	/**
	 * @return element for current type mirror
	 */
	@Decorate
	public Element getElement() {
		// get element from declared type or type variable
		DefaultElement element = null;
		if (typeMirror instanceof DeclaredType) {
			element = (DefaultElement) ((DeclaredType) typeMirror).asElement();
		}
		if (typeMirror instanceof TypeVariable) {
			element = (DefaultElement) ((TypeVariable) typeMirror).asElement();
		}
		if (typeMirror instanceof WildcardType) {
			element = (DefaultElement) ((DefaultDeclaredType) ((WildcardType) typeMirror)
					.getExtendsBound()).asElement();
		}

		// check if element is a generic type element or generic definition
		if (element instanceof DefaultTypeElement) {
			return (DefaultTypeElement) element;
		} else if (element instanceof DefaultTypeParameterElement) {
			List<? extends TypeMirror> bounds = ((DefaultTypeParameterElement) element)
					.getBounds();
			if (bounds.size() > 0) {
				if (bounds.size() > 1) {
					throw new GeneratorException("Check why we have multiple bounds!!!");
				} else {
					return (DefaultTypeElement) ((DefaultDeclaredType) bounds.get(0))
							.asElement();
				}
			} else {
				throw new GeneratorException("Bounds for type " + element
						+ " are not defined! Define e.g. <L extends Layer>");
			}
		}
		return null;
	}
	
}
